Portable light bulb



FIG. 1 is a first perspective view from above of a portable light bulb showing my new design;

FIG. 2 is a left side view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a back view thereof;

FIG. 7 is a right side view thereof;

FIG. 8 is a perspective view of a suction cup fitted into one of a plurality of slots for attachment purpose;

FIG. 9 is a perspective view of hanging the portable light bulb via a string and a magnet paired with one of a plurality of positions on the portable light bulb; and,

FIG. 10 is a second perspective view from below of the portable light bulb.

Broken lines are for illustration purposes and form no part of the claimed design. 

CLAIM The ornamental design for a portable light bulb, as shown and described. 